<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <button id="ka">kathy</button>
    <button id="zz">zzy</button>
    <button id="ex">exit</button>
    <img src="" alt="">
</body>
</html>
<script>
    var ka1 = document.getElementById("ka");
    var zz1 = document.getElementById("zz");
    var ex1 = document.getElementById("ex");
    var img1 = document.querySelector("img");
    ka1.onclick=function(){
        img1.src='imgs/1.jpg';
    }
    zz1.onclick=function(){
        img1.src='imgs/2.jpg';
    }
    ex1.onclick=function(){
        img1.src='';
    }
</script>
